Fusible motion arrestor



Jan. 31, NEWTON FUSIBLE MOTION ARRESTOR Filed July 20, 1953 INVENTOR.

26 F I e- 5 Sfqn/ey E. Newton BY wfii FIG-4 ATTORNEY United StatesPatent 2,732,920 FUSIBLE MOTION ARRESTOR Stanley E. Newton, Spokane,Wash.

Application July 20, 1953, Serial No. 369,002 7 Claims. (Cl. 189-45)This invention' relates to heat sensitive devices and more particularlyto a fusible motion arrestor. One object of'the invention is to providea fusible motion arrestor which is adapted to be employed with a closureOperating device to arrest the movement of the device and defer movementof the closure to a closed position until a temperature capable offusing the arrestor is present.

Another object of the invention lies in the provision of a fusiblemotion arrestor having a flat body provided with an opening adapted toencircle the reciprocating rod of a closing device in a barely loose fitand the body having a distortion disposed to tilt the arrestor andeffect binding of the rod; the distortion being maintained by fusiblematerial.

' Another object of the invention lies in the provision of a closureoperating device of the cylinder type having a piston reciprocablycarried therein and carrying a piston rod extending outwardly through ahead of the cylinder and a fusible motion arrestor disposed intermediatethe piston rod and said head whereby movement of the rod is deferreduntil the arrestor is fused.

Another object of the invention lies in the provision of a fusiblemotion arrestor having a body formed of a number of pliant rings formedinto a rigid unit by means of a fusible binder.

Another object of the invention is to generally improve closureoperating devices which are adapted to move closures to a closedposition when a fire breaks out in a building and the temperaturereachesa predetermined degree.

Another object of the invention is to provide a fusible motion arrestorwhich is inexpensive to manufacture and which is positive in its releaseof a reciprocating rod when a predetermined fusing temperature isreached.

These and other objects of the invention will become apparent during thecourse of the following description.

In many municipalities it is becoming law that in buildings forinvalids, such as hospitals and sanitariums, within certain distancesfrom the fire escapes must be sealed shut or suitable fire actuatedclosure be provided to insure its closing in the event a fire breaks outin the building. Of course the access openings to the fire escape mustalways be usable and therefore it is required that a suitable closureoperating device be associated with fire escape access openings.

In most instances it is desirable that openings at, or adjacent to fireescapes be in a position to be opened for purposes of ventilation andbecause of the expensive apparatus now on the market for this purpose,the present invention has been devised, making it possible to installautomatic closure operating devices at a minimum cost.

In the accompanying drawings forming a part of this specification, andin which like numerals are employed to designate like parts;

Figure 1 is a plan view of a closure operating device having a fusiblemotion arrestor associated therewith and securing the piston rod in theextended position;

Figure 2 is an enlarged fragmentary view showing a "ice portion of thepiston rod and its associated head and a fusible motion arrestor incross-section;

Figure 3 is a vertical cross section of a modified type of motionarrestor;

Figure 4 is a vertical cross section of a still further modification inthe fusible motion arrestor;

Figure 5 is a side elevation of a fusible motion arrestor showing astill further modification;

Figure 6 is a view in perspective showing another modified form offusible motion arrestor; and

Figure 7 is a view in perspective showing a portion of the piston rod,cylinder, and associated head in which another modification employingthe principles of this invention is shown. I

Broadly speaking, the essence of this invention lies in the fusiblemotion arrestor indicated in general by the numeral 10 and this may takeone of a number of forms as indicated by the modifications exemplifiedin the drawings.

I am well aware of the fact that prior to my invention fusible materialshave been employed in forming links for releasing sliding doors whenheated to a predetermined fusion temperature and also for actuatingrelatively expensive door checks of the liquid containing type. It is,however, my purpose to provide a door check or closure operating devicewhich is relatively inexpensive and which makes it practical in theapplication to buildings having a large number of openings near fireescapes.

The closure operating device which I. have found to be most practicalfor this application is illustrated in Figures 1 and 7 as having acylinder 11 provided with heads 12 and 13 at opposed ends. A piston 14is disposed within the cylinder and reciprocable therein. The piston isprovided with a piston rod 15 which extends outwardly through the head13 and is reciprocably mounted in a bearing 16 carried by the head 13.An expansion spring 17 is interposed the head 13 and the piston 14 urgesthe piston toward the rear head 12 wherein the piston rod 15 istelescoped within the cylinder 11.

Inspection of Figure 1 will show that the head 13 is provided with anenlarged vent 17 which permits escape of: air in advance of the piston14 as the closure is opened drawing the piston rod 15 outof the cylinderand moving the piston 14 forwardly. A restricted vent 18 is provided inthe rear head 12 and limits the telescopic movement of the piston rod 15to a constant speed commensurate with the escape of air confined betweenthe piston 14 and the head 12.

The outer end of the piston rod 15 is provided with a T-fitting 19 whichis pivotally secured to brackets 20 adapted to be fastened to a door,hinged window, or other closure and the head 12 is provided with abracket 21 adapted to be secured to a fixed element relative to theclosure to enable the closing device to shift the closure to a closedposition.

The fusible motion arrestor 10 is shown in Figure 2 as comprising anumber of pliant, fiat rings 22 which in themselves do not have the bodystrength required to prevent their being distorted by even slightpressures and these rings 22 are formed into a rigid unit by means of afusible binder 23 disposed intermediate each ring, and soldering therings one to another. 1 have shown three pliant rings 22, however, itwill be understood that any number of rings found necessary will be usedto provide a rigid, unitary arrestor having the body strength requiredto lock the piston rod 15 against telescopic movement with the cylinder11. Inspection of Figure 2 will show that a marginal edge portion of thearrestor is bent at an angle from the plane of the body forming adistortion or lip 24 which is presented toward the head 13 of theclosing device.

A central opening 25 is formed in the body of the arrestor 10 and iscircular to coincide with the peripheral shape of the piston rod 15. Itwill be noted that the size of the opening is such as to provide abarely loose fit about the piston rod 15. I use the phrase, barely loosefit, to indicate that the arrestor is loosely mounted upon the pistonrod for movement axially thereon and yet is small enough that when thearrestor is tilted out of a plane at right angles to the axis of thepiston rod 15, the sharp edges 26 will frictionally engage the pistonrod and prevent its movement longitudinally through the arrestor.

In Figure 3 I have shown a motion arrestor havinga body of any materialdesired, such as steel, and soldered thereon I have provided adistortion or boss 28 which is secured to a plane face of the arrestorbody and IS disposed in axial parallel relation to the opening 25.

In Figure 4 I have shown the motion arrestor as being formed completelyfrom a fusible metal and having a fiat ring shaped body 29 provided witha distortion or lip 30 disposed out of the plane of the body.

In Figure I have shown that the motion arrestor may have a radiallyextending cut 31 in the body 32 similar to that of a common lock washerand one end of the body adjacent the cut may be bent or distorted toform a lip 33 out of the plane of the body 32.

In Figure 6 I have shown the motion arrestor as taking the form of aflat ring comprising two substantially semi-circular sections 34 and 35fused together by means of fusionable material at 36 to maintain thedistortion or lip 37 at a constant position relative to the body.

Reference to Figure 7 will show that the motion arrestor may takeanother form, not having the distortion and as such the arrestor maytake the form of a U or be circular-as indicated at 38 of Figure 7. Inthis form the piston rod 39 is provided with one or more recesses 40 inwhich the motion arrestor 38 will fit and lock the piston rod 39 againsttelescopic movement into the cylinder 11. When a predeterminedtemperature is reached and the motion arrestor 38 fuses or melts, thepiston rod 39 is released to move into the cylinder thus closing theclosure.

The fusible material adaptable for use in connection with this inventionmay be one of the many common alloys presently used for fusible linksand the temperature at which the arrestor will fuse may be varied byincreasing or decreasing the ratio of metals in the alloy. This iscommon knowledge among those skilled in this particular art and will notbe dealt with in detail here. It is, however, feasible that plastics andother materials not yet discovered may be found practical in this useand therefore, it is not my intention to limit my inven- I limited onlyby the appended claims and in view of the 5 prior art.

Having thus described my invention, I claim:

1. In a closure operating device having a reciprocable rod biased tomove a closure to the closed position during telescopic movement into asecond element of the device, means for deferring said telescopicmovement until a predetermined temperature is present comprising a fiatring having a central bore encircling said rod in a barely loose fit;said ring having a distortion maintained by material fusible at saidpredetermined temperature and disposed to bear against said secondelement and effect frictional binding of the rod in said bore until saidfusing action.

2. As an article of manufacture, a fusible motion arrester forcontrolling the biased movement of a reciprocating rod of a closingdevice comprising a flat body hav ing an opening encircling saidreciprocating rod of a closing device in a barely loose fit; and saidbody having a distortion maintained by material fusible at apredetermined temperature and disposed out of the plane of the bodysufficiently to tilt the arrestor to effect the binding of the rod inthe opening when the distortion bears against the fixed surface relativeto the rod.

3. The invention as defined in claim 2 wherein the opening is providedwith sharp edges for frictionally engaging the peripheral face of therod and binding the rod against longitudinal movement therethrough.

4. The invention as defined in claim 2 wherein the distortion is a massof fusible material fixed to a plane face of said body and disposedaxially parallel with said opening.

5. The invention as defined in claim 2 wherein the body is formed offusible material and the distortion is provided by forming a portion ofthe body out of the plane thereof.

6. The invention as defined in claim 2 wherein the distortion is fixedrelative to the body by means of the fusible material soldering theelements together.

7. A heat sensitive closure operating device comprising a cylinderhaving heads at its ends; a piston longitudinally moveable within thecylinder and having a piston rod extending outwardly through one saidhead, an expansion spring encircling the piston rod and disposedintermediate the piston and one said head; securing means on the end ofsaid piston rod for securing the outer end thereof to a closure; meansfor securing the cylinder fixed relative to the closure; and meansfusible at a predetermined temperature and disposed intermediate thepiston rod and its companion head to effect binding of the rod andarrest telescopic movement thereof, urged by said spring.

References Cited in the file of this patent UNITED STATES PATENTS

